PUBLIC HEALTH ASSESSMENT
ROUTE 561 DUMP
UNITED STATES AVENUE BURN
GIBBSBORO, CAMDEN COUNTY, NEW JERSEY
This section contains discussion of the exposure pathways at the sites and their public health implications, if applicable. An exposure pathway is the process by which an individual is exposed to contaminants that originate from some source of contamination.
ATSDR/NJDHSS classifies exposure pathways into three groups: (1) completed pathways, that is, those in which exposure has occurred, is occurring, or will occur; (2) potential pathways, that is, those in which exposure might have occurred, may be occurring, or may yet occur; and (3) eliminated pathways, that is, those that can be eliminated from further analysis because one of the five elements is missing and will never be present, or in which no contaminants of concern can be identified.
A completed exposure pathway must include each of five elements that link a contaminant source to a receptor population. The five elements of a completed exposure pathway are the following:
- source of contamination;
- environmental media and transport mechanisms;
- point of exposure;
- route of exposure; and
- receptor population.
Health effects evaluations are accomplished by estimating the amount (or dose) of those contaminants that a person might come in contact with. This estimated exposure dose is then compared to established health guidelines. People who are exposed for some crucial length of time to contaminants of concern at levels above established guidelines are potentially more likely to have associated illnesses or disease.
Health guidelines are developed for contaminants commonly found at hazardous waste sites. Examples of health guidelines are the ATSDR's Minimal Risk Level (MRL) and the USEPA's Reference Dose (RfD). When exposure (or dose) is below the MRL or RfD, then non-cancer adverse health effects are unlikely to occur.
MRLs are developed for each type of exposure, such as acute (less than 14 days), intermediate (15 to 364 days), and chronic (365 days and greater). ATSDR presents these MRLs in Toxicological Profiles. These chemical-specific profiles provide information on health effects, environmental transport, human exposure, and regulatory status.
The toxicological effects of the contaminants detected in the environmental media have been considered singly. The cumulative or synergistic effects of mixtures of contaminants may serve to enhance their public health significance. Additionally, individual or mixtures of contaminants may have the ability to produce greater adverse health effects in children as compared to adults. This situation depends upon the specific chemical being ingested or inhaled, its pharmacokinetics in children and adults, and its toxicity in children and adults.
Under current site conditions, there are no documented ongoing human exposures to site-related soil contaminants. Past exposures to contaminated soil cannot be ruled out, but because it would be difficult to define a contaminant dose or identify an exposed population, no toxicological evaluation of this pathway will be performed. Surface soil contamination at the Route 561 Dump site exists at levels of public health concern if young children were to gain access to contaminated areas.
As noted above, during the site visit, the entire Route 561 Dump area was surrounded by a recently installed chain link fence, which appeared to be in good condition, making trespassing in this section difficult. In addition, a monitored security system has been installed at the site. Several of the most contaminated surface soil "hot spots" within the Route 561 site have been stabilized as an interim measure. Some of the contaminated surface soil areas were covered with membrane and clean soil, and then seeded. The potential for any human exposure to contaminated soils at the site has been greatly reduced, if not totally eliminated, by the installation of the new perimeter fence, interim partial capping, and the active security system.
The NJDEP collected sediment samples at the Route 561 Dump site on June 15, 1994. Three sediment samples were collected from the White Sand Branch. Analysis of the samples showed a progressive increase of lead concentrations from 16.6 mg/kg (upstream) to 364 mg/kg (downstream) and arsenic concentrations from 2.4 mg/kg (upstream) to 17 mg/kg (downstream). It is likely that sediment contamination at this site is related to or causing a more widespread problem with the streams and lakes in the vicinity; therefore, this must be considered a potential human exposure pathway. The Route 561 Dump site is upstream and connected by a series of streams and lakes to the United States Avenue Burn site and the newly discovered Hilliard's Creek site.
The NJDEP collected surface water samples at the Route 561 Dump site on June 15, 1994. Three surface water samples were collected from the White Sand Branch. Analysis of the samples showed a progressive increase of lead concentrations from 3.1 micrograms per liter (µg/l) (upstream), to 43.6 µg/l (downstream). As with the sediments, it is likely that surface water contamination at this site is related to the more widespread problem with contamination in some streams and lakes in the vicinity. Therefore, this must be considered a potential human exposure pathway.
The NJDEP collected shallow groundwater samples at the Route 561 Dump site in June 15, 1994 using a subsurface probe. Analysis of the samples showed the following concentrations; arsenic 3,790 µg/l, barium 6,970 µg/l, cadmium 14 µg/l, chromium 2,520 µg/l, copper 2,960 µg/l, cyanide 2,140 µg/l, lead 37,200 µg/l, nickel 1,440 µg/l, vanadium 814 µg/l, and zinc 2,730 µg/l. These groundwater samples were collected for screening purposes only and not for health and/or risk assessment purposes.
Currently, no data on potential contamination levels in deeper ground water are available.(8,9) Groundwater contamination also needs to be examined in terms of area wide environmental contamination at the United States Avenue Burn site and the Hilliard's Creek site.
There is a residential well within 200 feet of the Route 561 Dump site. Because this well is so close to the site there exists a potential for the well to become contaminated at levels of potential public health significance. The well was last checked in 1994 and was found to be free of site related contamination. However, the current quality of the water is unknown. The depth of the groundwater from which this residence draws water is also unknown. The direction of groundwater flow in the area needs to be discerned.
This section contains a discussion of contaminant levels found at the United States Avenue Burn site, and the possible health effects in adults and children exposed to those contaminants. The contaminant levels used in this public health assessment are from a field sampling event at the site conducted by Roy F. Weston, Inc.(14) Samples were collected in 1995 and 1996.
The Sherwin-Williams Company's environmental consultant, Roy F. Weston, Inc., has done extensive soil sampling to identify contamination at the site.(14)Analysis of on-site surface and sub-surface soil samples showed the presence of numerous heavy metals contaminants, including high levels of lead. Lead was detected in 223 of the 532 soil samples collected. Lead concentrations ranged from undetected to a maximum level of 244,000 mg/kg at 4 to 4.5 feet below the surface. In surface soil samples (0 to 6") lead concentrations ranged from undetected to 51,700 mg/kg. (14)
Other contaminants found in soil samples at levels above ATSDR soil comparison levels included: arsenic (maximum level 264 mg/kg); hexavalent chromium (maximum level 311 mg/kg); barium (maximum level 9,230 mg/kg); and zinc (maximum level 98,500 mg/kg).
The results of the sampling are summarized below in Table 1.
|Chromium (hexavalent)||311||300||Child RMEG***|
** EMEG: Environmental Media Evaluation Guide (ATSDR)
***RMEG: Reference Dose Media Evaluation Guide
****NE - Not Established. The NJDEP has established a Soil Cleanup Criteria level at 400 mg/kg for residential properties, and 600 mg/kg for non-residential properties.
Although there are currently no known completed human exposure pathways at the United States Avenue Burn site, trespassing in the past constitutes a completed exposure pathway. The NJDHSS/ATSDR has conducted two Public Health Consultations at the United States Avenue Burn site and two data reviews between 1995 and 1997. These documents were written prior to the recent installation of the security and fencing systems at the site. Analysis of site data and direct site observation have indicated that a completed human exposure pathway existed in the past among trespassers exposed to lead in soil. Trespassers using all-terrain vehicles and dirt bikes were known to have used the United States Avenue Burn site prior to the installation of the chain-link fence in 1997. The surface soil and waste material in this area are friable and easily dispersed.
Although the maximum concentration of lead detected in soil was 244,000 mg/kg, this concentration was only found in sub-surface soil at a depth of 4 - 4.5 feet. The highest level of lead found in surface soil was 51,700 mg/kg; however, this was in an area not easily accessible. The maximum lead contamination value (42,200 mg/kg) collected from surface soil in an area known to be used by trespassers was used as the basis for the toxicological evaluation for the December 4, 1997 consultation.(13) In that document, the ATSDR and the NJDHSS concluded that the site represented a public health hazard in the past, based on available information and an analysis of exposure dose and duration. Adults utilizing the site were not likely to have been exposed to lead contamination at concentrations sufficient to constitute a public health hazard. Children, however, may have been exposed to levels of lead that may pose a public health hazard. Children are at higher risk from lead than adults because their developing systems are more susceptible to its effects. These effects can include decreased intelligence, learning disabilities, hearing loss, and behavioral problems in exposed children.
The NJDHSS has determined that trespassers on the site, in particular older children, could potentially be exposed to several contaminants in on-site surface soil. Under current site conditions, it is very unlikely that young children would enter the site, mostly due to the remoteness of the site and the inaccessibility of the area due to the 6' high chain-link fence. It is likely that trespassers would be either adults or older children capable of scaling the fence. This is unlikely to be a common occurrence. Most of the known contaminated areas of the United States Avenue Burn site are surrounded by a chain-link fence. As noted previously, the USEPA believes the fence currently encloses all known soil lead contamination above 400 mg/kg. It is possible, however, that the full extent of the site contamination was not delineated prior to the erection of the fence and some contaminated areas outside the fence may be accessible.
Under current site conditions, trespassers riding all-terrain vehicles and dirt bikes on the site no longer have open access to the heavily contaminated portions. The surface soil and waste material in this area remains friable and easily dispersed. The maximum concentration of lead (51,700 mg/kg) is still present in surface soil. This contaminated soil would be accessible to determined site trespassers, who would climb over or cut through the 6' chain-link fence. It is, however, unlikely that much, if any, trespassing has occurred on this site since it was enclosed.
Sediment samples were collected from water bodies (White Sands Branch, Haney Run Brook, and Bridgewood Lake) located upstream, downstream, and adjacent, respectively, to the United States Avenue Burn site. During its investigation, Weston collected a total of 38 sediment samples. Analysis of these sediment samples indicated the presence of lead (maximum level 14,700 mg/kg), arsenic (maximum level 162 mg/kg), cadmium (maximum level 3.5 mg/kg), mercury (maximum level 0.71 mg/kg), and zinc (maximum level 212 mg/kg).
In its report, Weston noted that in some cases the concentrations measured in upstream locations were higher than concentrations measured on-site. This indicates that contaminants may have migrated from another site (e.g. Route 561 Dump site). It also illustrates the need to investigate the sediment contamination at the United States Avenue Burn site as part of an area-wide investigation of this site, the Route 561 site, the Hilliard's Creek site, and possibly other undiscovered sites. Sediments, therefore, must be considered a potential human exposure pathway. Two sediment samples for lead were taken from Bridgewood Lake, which is downstream of the site. The lead levels in these samples were 1,420 and 1,360 mg/kg.
During its investigation, Weston collected 5 surface water samples at the site. Analysis of these surface water samples indicated the presence of lead in all five samples (maximum level 9.7 µg/l). As with the sediments at this site and other related sites, it is likely that surface water contamination at this site is related to the more widespread problem with contamination in some streams and lakes in the vicinity. Therefore, this must be considered a potential human exposure pathway.
Groundwater monitoring at the United States Avenue Burn site has not been thorough enough to fully characterize the depth and spread of the contamination. Sampling that has been performed confirms that the shallow groundwater has been contaminated by the site. Between August 1981 and December 1988 fourteen groundwater samples were taken from each of four monitoring wells located in the vicinity of the former landfill area. Lead was detected as high as 69,000 µg/l (Well #7, 4/17/85). Benzene has also been detected in groundwater. Well #9 showed benzene at 75.9 µg/l during sampling on 9/14/83.
During its investigation, Weston collected 5 groundwater samples at the site. Analysis of these groundwater samples indicated the presence of lead in two well locations (maximum level 112 µg/l). Also detected were; arsenic (maximum level 826 µg/l), cadmium (maximum level 4.1 µg/l), and manganese (maximum level 174 µg/l). Benzene has also been detected at 9 µg/l.
There is a residential well within 200 feet of this site. As with the Route 561 site, this well is so close to the site there exists a potential for it to become contaminated at levels of potential public health significance. At this time, no data on potential contamination levels in deeper ground water were available. The well was last checked in 1994 and was found to be free of site related contamination, however, the current quality of the water is unknown. The depth of the groundwater from which this residence draws water is also unknown. The direction of groundwater flow in the area needs to be discerned.
There are multiple sources of health outcome data in New Jersey. State and local data for heath outcome information include the New Jersey State Cancer Registry, Birth Defects Registry, Vital Statistics Records, Renal Dialysis Network, and Hospital Discharge Reports. However, because no exposed populations have been defined and the low number of possible individuals exposed, review of health outcome data in this case would not be appropriate. Therefore, no health outcome data were evaluated.
ATSDR's Child Health Initiative recognizes that the unique vulnerabilities of infants and children demand special emphasis in communities faced with contamination in their environment. Children are at greater risk than adults from certain kinds of exposures to hazardous substances emitted from a waste site. They are more likely to be exposed because they play outdoors and they often bring food into contaminated areas. They are shorter than adults, which means they breathe dust, soil, and heavy vapors closer to the ground. Children are also smaller, resulting in higher doses of chemical exposure per body weight. The developing body systems of children can sustain permanent damage if toxic exposures occur during critical growth stages. Children depend completely on adults for risk identification and management decisions, housing decisions, and access to medical care.
Children who may have frequented the United States Avenue Burn site in the past may have been exposed to lead at levels of public health concern. The surface soil at the sites has been contaminated with high levels of lead. Lead is harmful to children, especially children less than six years old. The areas of contaminated soil, however, are currently inaccessible to young children, making contact with contaminated surface soil very unlikely. The areas of contaminated soil would only be accessible to the most determined older children who may trespass on the sites.
In order to gather information on community health concerns at the Route 561 Dump site and the United States Avenue Burn site, NJDHSS spoke with the Camden County Health Department (CCHD) and its Environmental Health Division on 7/15/99. According to these local officials, community concerns have been minimal, possibly due to the sites' remoteness and the limited number of residents living near the sites. The CCHD was unaware of any childhood lead issues associated with the sites. The ATSDR/NJDHSS prepared a fact sheet concerning the two sites (January, 1998). A draft of this document was distributed to the CCHD.
A Public Comment period occurred from June 19 through July 19, 2000. No comments were received during that time.